The aim of the study was to examine and compare oxidative stability of refined (peanut, corn, rice bran, grapeseed, and rapeseed) oils. The oils were subject a Schaal Oven Test (temperature 63 ± 1 °C) and a Rancimat test (temperature 120 °C) and their stability was compared at the 1st and 12th month of storage. Changes in the peroxide (PV) and anisidine (AnV) values in the thermostat test were the fastest in rapeseed oil and grapeseed oil. The best quality was preserved by peanut and corn oils both in the first and the twelfth month of storage. The induction times for the rice bran, corn, peanut, and rapeseed oils were similar from 4.77 h to 5.02 h in the first month and from 3.22 h to 3.77 h in the twelfth month. The shortest induction times were determined for grapeseed oil: 2.4 h and 1.6 h, respectively. A decrease of oxidative stability of about 30% was found in all the oils after 12 months of storage. The PV of 10, determined in the thermostat and Rancimat tests, were achieved at the latest in corn oil and the fastest in rice bran oil.

The aim of the study was to analyze the effect of the type of gelling substance on the selected physicochemical properties of oleogels. Rapeseed oil (RO) and 5% w/w of one of the following structuring compounds (SC) were used for their production waxes: sunflower (SUN), candelilla (CAN), bees white (BW), bees yellow (BY), or monoacylglycerols (MAG). The ability of SC to form a network in RO was assessed on the basis of an analysis of the texture of oleogels (hardness and spreadability test, stability determined by the centrifugal method). Oxidative stability was determined using the Rancimat test. In addition, the microstructure of an oleogel samples was observed at a magnification of 600 times in polarized light and in a bright field. Differences in the brightness and color of the samples were also assessed using the CIELab reflection method. The highest hardness (5.52 N) and physical stability (99.67%) were found in oleogel with candelilla wax. A higher value of the force causing deformation of the sample indicates a denser network of oil gel, which was confirmed by the microscopic images analyzed in the work. The organogel with CAN had the shortest (on average 8.49 nm) and the most regularly distributed crystals compared to other samples. The lowest values of organogel strength and spreadability test parameters (e.g., firmness, work of shear, stickness, work of adhesion), which were respectively 0.73 N, 4.39 N, and 9.74 N mm, while −4.87 N and −2.68 N mm were obtained with the variant, which was yellow beeswax. Considering the texture results obtained and the centrifugal stability, it was found that organogels with yellow beeswax were characterized by the worst structuring of rapeseed oil. Sunflower wax was considered the best among the analyzed gelling agents (under the conditions of the experiment). The organogel with its 5% w/w share was distinguished by the closest to the white color and texture most reminiscent of cream. In addition, it had the highest work of shear value and the longest induction time (6.8 h) in the Rancimat test.

Food labelled with a “best before” date has a long shelf life. This study aimed to examine the respondents’ knowledge and understanding regarding the labelling on food products, as well as to assess the microbiological, physico–chemical and the sensory quality of selected durable food products on and after the date specified by the manufacturer. Two methods were used—a survey and laboratory tests. It was found that the majority of respondents have difficulty distinguishing and understanding the terms on the label and that a significant proportion of the respondents consume food products after the “best before” date. Laboratory tests of milk, pasta, mayonnaise and jam confirmed the microbiological safety of the products even six months after the “best before” date. Other features (texture, colour and sensory quality) slightly changed after one month for milk and mayonnaise (the colour had become more yellow) and after three months for pasta (its hardness had decreased) and jam (it had become browner). The possibility of extending the “best before” dates of selected durable foods could be considered, which could allow such products to legally be handed over to public benefit organisations, thereby reducing food wastage.

The aim of the work was to determine the impact of addition of transglutaminase (TGase), soy and whey protein on physicochemical and sensory properties of gluten-free breads. Samples were produced from concentrates consist of 7% of soy or whey protein. TGase was added in amount of 1, and 10 U/g of protein. Following features have been marked for each gluten-free bread sample: specific mass, specific volume, crumb porosity, moisture and crumb hardness. One observed that more valuable changes have been observed for the samples with soy protein; in particular, addition of 1U/g of TGase to gluten-free breads with soy or whey protein improves several physicochemical and sensory features of gluten-free breads. An impact of TGase into quality of gluten-free breads depends on the type of proteins that has been used. Samples with addition of 1U TGase were better assessed by consumers in comparison with other analyzed samples.

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